Boundary entropy under ambient RG flow in the AdS/BCFT model

Abstract

We discuss the change of the boundary entropy under an ambient renormalization group flow. We use conformal perturbation theory to calculate the change of the boundary entropy for $d$-dimensional BCFTs between two nearby fixed points. We also use the AdS$_{d+1}$/BCFT$_d$ model to calculate the boundary entropy. We show that the boundary entropy can increase under the ambient RG flow both in conformal perturbation theory and the AdS$_{d+1}$/BCFT$_d$ model. In a special case, the change of the boundary entropy in the AdS$_{d+1}$/BCFT$_d$ model reduces to that of the conformal perturbation theory.